A comparison of three cell types as potential candidates for intervertebral disc therapy: annulus fibrosus cells, chondrocytes, and bone marrow derived cells.
OBJECTIVE
Candidate cell types for disc cell transplantation therapy include anulus fibrosus (AF) cells, chondrocytes, and bone marrow derived cells (BMDCs). We compared the disc matrix production in these three types of cells, before and after stimulation with rhBMP-2. There is no study extant that compares these three cell types to determine the best candidate for the disc cell therapy.


METHODS
AF cells, chondrocytes, and BMDCs (iliac crest and femur) were isolated and grown in monolayer. They were treated for 3 days with rhBMP-2. After 3 days, proteoglycan (sGAG) content in the media was quantified. The results were normalized by cell numbers. The mRNA expression of aggrecan, type I collagen, and type II collagen was measured using real-time PCR. Each cell type was also cultured in chamber slides and immunostained for aggrecan, type I collagen, and type II collagen after 3 days of treatment with rhBMP-2.


RESULTS
(1) Without rhBMP-2 the chondrocytes produced more proteoglycan (sGAG) as compared to the other two cell types (AF cells and BMDCs). After stimulation with rhBMP-2 the chondrocytes produce even more proteoglycan than the other two cell types. (2) As compared to the other two cell types, in terms of mRNA expression, the chondrocytes expressed more aggrecan, type I collagen, and type II collagen before stimulation with rhBMP-2. After rhBMP-2 stimulation, the chondrocytes expressed even more aggrecan, type I collagen, and type II collagen in proportion to the concentration of rhBMP-2. For the BMDCs there were no changes in type I and II collagen. (3) rhBMP-2 stimulation produced increases in the protein levels of aggrecan, type I and II collagen in all three types of cells.


CONCLUSIONS
On balance, according to these results, it would seem that chondrocytes are the best candidate for the disc cell therapy.
Kuh
Sung Uk
SU
Department of Neurosurgery, Yonsei University Medical College, Spine and Spinal Cord Institute, Seoul, South Korea.
Zhu
Yerun
Y
Li
Jun
J
Tsai
Kai-Jow
KJ
Fei
Qinming
Q
Hutton
William C
WC
Yoon
Tim S
TS
D053674:Aggrecans / Q000235:genetics / Q000378:metabolism; D000818:Animals; D001854:Bone Marrow Cells / Q000166:cytology* / Q000378:metabolism; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins / Q000494:pharmacology; D002358:Cartilage, Articular / Q000166:cytology / Q000187:drug effects; D017690:Cell Transplantation / Q000379:methods*; D002478:Cells, Cultured; D019902:Chondrocytes / Q000166:cytology* / Q000378:metabolism; D024042:Collagen Type I / Q000235:genetics / Q000378:metabolism; D024043:Collagen Type II / Q000235:genetics / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D016326:Extracellular Matrix Proteins / Q000096:biosynthesis / Q000187:drug effects; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D006025:Glycosaminoglycans / Q000096:biosynthesis; D007403:Intervertebral Disc / Q000166:cytology* / Q000378:metabolism; D007405:Intervertebral Disc Displacement / Q000473:pathology / Q000628:therapy*; D012333:RNA, Messenger / Q000378:metabolism; D011817:Rabbits; D011994:Recombinant Proteins / Q000494:pharmacology; D016212:Transforming Growth Factor beta / Q000494:pharmacology
D053674:Aggrecans; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D024042:Collagen Type I; D024043:Collagen Type II; D016326:Extracellular Matrix Proteins; D006025:Glycosaminoglycans; D012333:RNA, Messenger; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta; C499469:recombinant human bone morphogenetic protein-2; C013786:A73025